The goals of this project are the detection, quantification and grading of atherosclerosis using information obtained from real time spectral analysis of C.W. Doppler waveforms obtained in human and animal subjects. Experiments have been carried out in bench models and animals and non-invasive data have been collected from healthy and atherosclerotic subjects. This information is now being correlated with clinical and angiographic data which has been encoded in a large computer. Subgroup identification by cross correlation of numerical and clinical data with relevant statistics are the ultimate goal of this year's effort.